Imran Muhammad, Mix Andreas, Neumann Beate, Stammler Hans-Georg, Monkowius Uwe, Bleckenwegner Petra, Mitzel Norbert W
Universität Bielefeld, Lehrstuhl für Anorganische Chemie und Strukturchemie, Centrum für Molekulare Materialien, CM2, Universitätsstraße 25, 33615 Bielefeld, Germany.
Dalton Trans. 2014 Jul 28;43(28):10956-68. doi: 10.1039/c4dt00668b.
Some novel complexes of bismuth(III) with the Janus scorpionate ligand HB(mtda(Me))3 (mtda(Me) = 2-mercapto-5-methyl-1,3,4-thiadiazolyl) were synthesised. Na[HB(mtda(Me))3] (1) was reacted with BiX3 (X = Cl, I, NO3) in the molar ratio 2 : 1 to afford the bismuth complexes {HB(mtda(Me))3}2BiCl (3), Na[{HB(mtda(Me))3}2BiI2] (4) and [{HB(mtda(Me))3}2Bi(NO3)]n (5). Two mixed complexes {HB(mtda(Me))3}Bi(phen)Cl2 (6) and {HB(mtda(Me))3}Bi(bipy)Cl2 (7) were obtained using Janus scorpionate as the primary ligand in the presence of 1,10-phenanthroline and 2,2'-bipyridyl, respectively, as co-ligands in the 1 : 1 ratio. The obtained complexes were characterised by (1)H, (13)C and diffusion NMR (DOSY), elemental analyses and mass spectrometry. Structures of the compounds NBu4[HB(mtda(Me))3] (2), 3, 4, 5, 6 and 7 were determined by single crystal X-ray diffraction. The molecular dynamic process in complex 3 was also studied by variable temperature NMR measurements. All bismuth complexes, except for the polymeric 5, are monomeric. Complexes 6 and 7 exhibit (B)H···Bi distances of 2.76(3) and 2.71(2) Å length, respectively. Compounds 2, 6 and 7 were screened for their luminescence activity. At 77 K in ethanol solution, complexes 6 and 7 exhibit phosphorescence from ligand-to-ligand charge transfer (LLCT) and the ligand-centred (LC) excited state, respectively.
